Bug when taking notes on top of a PDF

When reading an PDF and taking notes on top of it, the PDF gets resized to a bit smaller, so one cannot write on the corners of the screen. Would it be possible to draw the boundaries of the PDF on screen, so that the users may know where they are allowed to take notes and where they are not?

I noticed the boundary is draw, but when you erase something with the stylus, the boundary disappears. Please fix.

Since it seems to be a bug I renamed it accordingly.
Version: 2018-12-26_18-59_2.0.1_0d1b2fc

Hello, thank you for your feedback. Yes, it has a boundary, and we have forwarded this to our relative colleagues to follow up.